However if at the end of a round you choose to leave then that is it you can't re-enter unless you start from the beginning and pay 15 nrg again.

But if you die then you lose the prize.

What I mean is after 1st fight you get the option of 50 silver - take it or leave it. If you take it then you exit the arena if you leave it then you battle again and are given 100 silver take it or leave it etc.